13. Mortgages Payable:
During 2013, the Company (i) assumed $284.9 million of individual non-recourse mortgage debt relating to the acquisition of nine operating properties, including an increase of $5.8 million associated with fair value debt adjustments, (ii) paid off $256.3 million of mortgage debt that encumbered 14 properties and (iii) obtained $36.0 million of individual non-recourse debt relating to three operating properties.
During 2012, the Company (i) assumed $185.3 million of individual non-recourse mortgage debt relating to the acquisition of seven operating properties, including an increase of $6.1 million associated with fair value debt adjustments, (ii) paid off $284.8 million of mortgage debt that encumbered 19 properties and (iii) assigned five mortgages aggregating $17.1 million in connection with property dispositions.
Mortgages payable, collateralized by certain shopping center properties and related tenants' leases, are generally due in monthly installments of principal and/or interest, which mature at various dates through 2035. Interest rates range from LIBOR (0.14% as of December 31, 2013) to 9.75% (weighted-average interest rate of 5.88% as of December 31, 2013). The scheduled principal payments (excluding any extension options available to the Company) of all mortgages payable, excluding unamortized fair value debt adjustments of $10.7 million, as of December 31, 2013, were as follows (in millions): 2014, $143.5; 2015, $176.2; 2016, $291.2; 2017, $178.0; 2018, $54.9 and thereafter, $180.9.